This invention relates to ignition cables used in the ignition circuits of the internal combustion engines of automobiles, and more particularly to a wire-wound type high voltage resistance cable.
Typically, electro-magnetic noises from automobiles using gasoline engines are liable to interfere with the signal receiver of radio sets, television sets or mobile radio stations mounted within the automobile. In order to suppress these noises, the ignition cables of the internal combustion engine of an automobile are typically composed of a noise preventive wire. The main purpose of an ignition cable is to transmit a high voltage from the secondary side of an ignition coil to the ignition plug, without reducing the voltage level in transit, and perform firing of the ignition plug perfectly. Another important purpose of the ignition cable is to attenuate the capacity discharging current which flows during the initial period of ignition plug discharge. The frequency component of this capacity discharging current ranges from the MF band to the UHF band because the rise speed of the current is very high (10.sup.-9 sec.). This discharging current component is the main cause of the production of noise waves. Since there has been a strong demand for the use of the 80 MHz frequency band as a communications channel, it is especially necessary to suppress the noises in this frequency band.